4thPeriod AnnouncementsHello 4thperiod. I have graded your lab packetsand your debate worksheets which were out of50. Im pleased to say the class average on thedebate worksheet was about 45. Today, pleasebe on your best behavior as we finish up acidsand bases and work on our project. We will spendmore time on it Tuesday and I will be checking inwith each group to make sure you are on track.Have a great day!-Mr. Lee
Warm-up (5 min to answer, 5 minto discuss)Please answer the following questions in yourinteractive notebook:1) What do you think would happen if you mixedan acid and a base together?2) Carbon Dioxide reacts with water to form aweak acid. Increased amounts of CO2 in our air isdissolving into the water in our oceans. Whateffects do you think increasing acidity of oceanwater has?
NotesWe will answer the warm-up questions and morethrough the next several slides. For now, pleaseset up your Cornell notes with theFocus Question: What are acids and bases? Whydoes the indicator change colors?Please copy notes in green
Part 1/3: Lap RecapWhat we should have seen in the lab on Tuesdaywas the colors changing as we added strongeracid and base solutionsscoops of citric acid color ph0 Green 71 Yellow-green 6.52 Yellow 63 Light orange 5.54 Peach 55 Pink 4
Reason: The more citric acid you add to the 5mlof water, the more concentrated with acid itbecame.Concentrated: describes the amount ofsolute in the solution
A solution includes a solute and a solventA solute is what is dissolvedA solvent is what does the dissolvingWhen you add alka-seltzer to a cup,the alka-seltzer is the solute,the water is the solvent,and the resulting drink is a solution
For the basic (sodium carbonate solution), youshouldve seen the colors become darkerNumber of scoops Color pH0 Green 71 Green-blue 82 Blue 8.53 Blue-purple 94 Purple 9.55 Purple 10
Question: What happened to the concentration ofthe basic solution as you added more sodiumcarbonate?
Part 2/3: WaterWhy did the indicator molecule change color inthe first place? Well first, we have to take a look atwhat the water molecules are constantly doing
You must first know that at any point in time,water molecules are constantly bumping into eachother and trading H+ atoms, which we call protons
H20 molecules bump into each other and onemolecule takes a H+ from the other molecule
Afterward, the molecule that received the extra H+gives it back to the other molecule, returning themboth to H20. This back-and-forth happens so thatthere are an equal # of H3o+ and OH- ions
Play this animationhttp://www.middleschoolchemistry.com/multimedia/chapter6/lesson8#proton_transfer
Water molecules bump into each other and tradeprotons, changing between H20 molecules andH30+ and OH- ions
Gravy? Now, lets learn the definition of acids andbasesAcid: a substance that donates H+ ions into thesolutionBase: a substance that accepts H+ in the solution
So when an acid is added to a solution, more H+are added. Therefore, it increases the number ofH3o+ molecules in the solution.A base accepts H+ ions, so there will be moreOH- ions in the solution.
Think-Pair-ShareMid-way quiz. Discuss with your elbow partnerand Ms. Esparza will choose 3 students to answer1) What 2 molecules do H20 molecules constantlychange into?2) What atom do the H20 molecules trade?3) When you add a base to a solution, whathappens?
1) H20 molecules change into H30+ and OH- ions2) H20 molecules trade the H+ atom3) A base accepts H+ ions and increases theamount of OH- ions in the solution
Part 3/3: Indicator moleculeSo why does this change the color?An indicator molecule is a special molecule thatchanges color depending on the amount of H3O+and OH- ions in the solution.If the amount of H30+ and OH- are balanced, itwill stay greenIf there are more H3O+ molecules than OH-, it willaccept the extra H+ ions and change from greento yellow to redIf there are more OH- molecules than H30+, it willdonate a H+ to the water molecules and changefrom green to blue to purple
Watch the animation:http://www.middleschoolchemistry.com/multimedia/chH3O+ > OH- : lowers the pHH30+ < OH- : raises the pHH30+ = OH- : pH = 7
Gravy? Ok an additional pointWhen acids and bases combine, they willneutralize each other. Which means if you mix abasic (blue) solution with an acidic (yellow)solution, it will return to green with the indicatorIf either the base or acid is a little stronger, thecolor will shift more to that side
Why its importantCarbon Dioxide can react with water to create aweak acid.The increasing Carbon Dioxide in our air fromglobal emissions is dissolving into our oceanwater and creating more acidic ocean water.This leads to coral bleaching, which can lead to achain reaction of events...more on this next week
Assignment: 20 min. 25 pointsComplete one of the following in your interactivenotebook1: Draw a picture and provide a 5+ sentenceexplanation of what made the solutions in our labchange color.2. Draw a comic that also explains how colorchanges in an indicator solution based on whetheracids/bases are present
Project: Due at end of period andHWHere is whats due for each of the 4 types ofprojects. Please write down what is due foryour specific project.Your work today is worth 50 points. Please beforewarned that I will be very tough on grading thework you turn in today.Your homework assignment is worth an additional20 points
Childrens Book groupsDue at end of period: Draft of 10 pages that youwill have in your book, complete with illustrationsHW: bring in a childrens book for next Tuesday
Presentation groupsDue at end of period: You must have a skit,poster, or powerpoint prepared. Create a roughdraft/script of this. Write a 1-page summary ofwhat you intend to teach students.HW: 1-page per student on research they havedone on their topic.
Science Project groupsDue at end of period: Written summary of yourQuestion, Hypothesis, Experiment, Materials. Alsoexplain what type of graph you will use to showyour results, and what physical object you willbring to presentHW: find samples of science projects online andprint and bring one to class per group
Lesson Plan groupsDue at end of period: Rough draft of powerpoint(draw/outline on paper what you will have on theslides), overhead sheets, quizzes, and handoutsyou will use for the lesson.HW: Think of a teaching strategy or method usedby your current or past teachers that you liked.Choose one and write half a page on how youcould implement it into your lesson (1 per person)
Sign-up sheetMs. Esparza will put up a sign up sheet for yourproject. I will start to meet with teachers to set uptimes for you to present your presentations andchildrens books. Lesson plans and scienceprojects will be presented in our class.Please fill out your names, project you havechosen, how it relates to science, and what agegroup you are creating the project for
ParticipationLastly, Ms. Esparza will be keeping track of thosewho are and are not off task. You can earn 20points for participation and she will award you withthem on her discretion.Have fun and use your time wisely!